Tuyere section for coal burning stokers



Sept. 18, 1934. M c. RICHARDSON 1,973,955

TUYERE SECTION FOR COAL BURNING STOKERS Filed April 22, 1930 2SheetsSheet l M.C. RKHARDSON 4 7- TERA/Ev Se t. 18, 1934. M. c.RICHARDSON TUYI BRE SEG'TION FOR COAL BURNING STOK ERS Filed April 22,1950 2 Sheets-Sheet 2 IIIATIIII/I/ 7 4 TTUR/VE/ Patented Sept. 18, 1934UNITED STATES I TUYERE SECTION FOR COAL BURNING STOKERS Max C.Richardson, Portland, 0reg., assignor to Iron Fireman ManufacturingCompany, Portland, Oreg.

Application April 22, 1930, Serial No. 446,207

4 Claims. (Cl. 110-45) This invention relates generally to coal burningstokers of the under feed type, and particularly to an improved form oftuyere section for use in connection with such devices.

The main object of this invention is to provide a tuyere or gratesection adapted for automatic ash removing which will provide themaximum amount of grate surface for a given size of combustion chamberin the furnace in which it is to be installed.

The second object is to construct a tuyere section which will be simpleto manufacture and assemble and which will facilitate the renewal ofdefective or damaged parts.

The third object is to provide a tuyere section having an outlet in itsperiphery for the escape of 'clinkers, and also the provision of a wallbetween said outlet and the center of the tuyere section for the purposeof permitting the maintenance of a fuel bed to a height equal to thatwhich could be maintained if no outlet opening were present.

The fourth object is to provide a slicing bar for breaking up andpulling clinkers from the fire bed.

The fifth object is to so construct the tuyere or grate section that itwill adapt itself to the reception of fuel from a feed screw and to theuniform distribution of fuel across the grate surface.

The sixth object is to construct a stratified tuyere section in whichthe sections are so constructed as to orient themselves with relation toeach other and to hold same concentric about the vertical axis of theretort, and at the same time provide a dependable locking means for thesections which will be devoid of screws or other parts not adapted towithstand the conditions commonly found within a combustion chamber.

These, and other objects, will become more apparent from thespecification following as illustrated in the accompanying drawings, inwhich:

Figure 1 is' a vertical section through the device.

Figure 2 is a perspective view of a tuyere section.

Figure 3 is a plan of the device with the connecting parts broken away.

Figure 4 is a horizontal section along the line 4-4 in Fig. 1.

Similar numbers of reference refer to similar parts throughout theseveral views.

Referring in detail to the drawings, there is shown a fuel feed duct 10of an underfeed stoker employing. a fuel feed screw 11 for the purposeof feeding coal upwardly through the retort section 12. Surrounding thesection 12 and integral therewith is a wall 13 upon which rests the ashtable 14, which extends outwardly from the wall 13 and inwardlytherefrom to the inner edge 15 of. the retort section 12. The under sideof the ash table 14 is provided with an annular rib 16 which occupies acorresponding recess in the section 12 for location purposes.

Rising from the ash table 14 directly above the wall 13 is an upturnedflange 1'7. On the outer edge of the ash table 14 is formed a similarupturned flange 18. Supported on brackets 19 on the wall 13 are thegrooved rollers 20 which support the ring gear 21 by engaging itsinturned track 22. employed in place of the ring gear. On the ring gear21 is secured a grinding ring 23 by means of the screws 24. The innerface 25 of the grinding ring 23 slopes inwardly and downwardly andterminates in a lip 26 which overhangs the flange 18. The face 25 isprovided with a plurality of grinding ribs 27 which preferably slope inthe direction indicated. It is desirable to provide ribs '28 on theouter side of the flange 17 to cooperate with the ribs 27.

Surrounding the grinding ring 23 is a cylindrical guard 29 whoseinwardly and downwardly turned upper edge 30 is employed to preventashes from finding their way into the driving mechanism of the grindingring 23. The lower end 31 of the member 29 is secured to the retortsection 12.

Mounted on top of the ash table 14, close to its inner edge 15, is aseries of annular tuyere sections 32, 33, 34 and 34A. The under sides ofthe sections 33, 34 and 34A are provided with a plurality of radial lugs35 and 36. The lugs 36 are slightly longer than the lugs 35 and extendinto the corresponding recesses 37 in the next section below. The underside of the section 32 is provided. with an annular groove 38 to receivethe annular rib 39 on the top side of the table 14.

On top of the section 34A and the flange 17 rests the tuyere rim 40which is circular in shape and is provided with tuyere openings 41having connecting passageways 42 which connect with the plenum or airchamber 43 which is supplied with air from the air box 44 whose underside is preferably made tight by means of a floor plate 45.

The tuyere rim 40 is provided with an outwardly curving face 46, one ormore sides of which may be flattened off and provided with an upstandingwall 4''! having a curved top edge 48 and a shoulder 49 formed at oneend thereof.

Obviously an internal gear could be i The purpose of the curved top edge48, which is in reality but a cross section through a domeshaped mass offuel, is to support the fuel in exactly the same positon and shape asthough no portion of its horizontal supporting surface had been cutaway. The purpose of the shoulder 47 is to facilitate the breaking ofthe clinkers against the slicing member 54, which clinkers mightotherwise run up over the top of the curved surface 48 without beingbroken or pulled from the mass of fuel.

On the outside of the flange 17 are formed the lugs 50 which are adaptedto engage the hooks 51 extending from the rib arms 52 which are integralwith the rim 40. The purpose of these hooks is to permit the rim 40 tobe employed as a locking member for the various tuyere sections 32, 33,34 and 34-A, and the direction of locking corresponds with the directionof rotation of the ring 23.

It will be noted that, although the rim 40 is not a complete circle dueto the fact that space must be provided to permit the escape of theclinkers, it can readily be seen that, due to the presence of the wall47 and its location and angular position (as better shown in Fig. 3) theshape of the fuel bed 53 is substantially the same as it would be if therim 40 were a complete circle.

Secured to the ring 23 is a slicing member 54 which travels about theoutside of the rim 40 removing the over-hanging clinkers 55, and if theyreach the point where the shoulder 49 is located it serves to partiallybreak up the clinkers 55 allowing same to fall between the grinding ring23 and the flange 17. It will be noted that the under side of the rim 40is provided with the same lugs 35 as are the tuyre sections 33, 34 and34A.

At one point just beyond the wall 47 in the direction of rotation islocated an outlet opening 56 beneath which is positoned an ash removingworm 57 which is confined within a casing 58 and drives the grindingring 23 by means of the gears 59 and 60 in any convenient manner.

It can be seen from the above that by this arrangement it is. possibleto secure a greater outside diameter for the rim 40 and therefore agreater burning surface from a given diameter of boiler or furnace. Thisis of special importance where the capacity of the heating element isalready taxed and it is not desired to sacrifice grate surface for thepurpose of employing an ash remover.

It will be noted that in the drawings there is shown only one wall 47and that its position is at the farthermost end of the retort justpreceding the outlet opening 56. It must be understood that in someinstances it may be found desirable to employ more than one wall. Thesame is true of the construction of the tuyre sections 32, 33 and 34 andthe manner in which they are held concentric 'with relation to eachother. Obviously, the number of slots may be varied without departingfrom the spirit of this invention and the drawings are merely intendedto illustrate the preferred form and are not intended to limit the scopeof the appended claims.

I claim: I 1. An annular tuyere' section having a. plurality of radialslots formed in one face thereof, the other face having a plurality ofspaced radial lugs formed thereon providing air passages therebetweensome of which lugs are of greater length than are the others for thepurpose of occupying slots in the next adjacent section.

2. A stoker fire pot having in combination a stationary tuyere rimsurmounted thereon; said rim having a raised flattened side formed onits outer edge, a rotary grinding ring spaced from and encircling saidfire pot, an upright slicer bar carried by said ring, and means torotate said ring whereby said bar co-acts with said flattened side tocrush clinkers therebetween.

3. A retort comprising a plurality of annular tuyere rings having radiallugs projecting unequal distances from one side thereof and havingradial slots formed in the opposite side thereof whereby the longer lugsof one section engage the slots of the next adjacent section for thepurpose of holding the same in superimposed coaxial relationship andforming tuyere openings between said sections.

4. A stoker fire pot having in combination a stationary annular tuyrerim surmounted thereon; said rim having a raised flattened side formedon its outer edge, a rotatable grinding ring spaced from and encirclingsaid rim, and means for rotating said ring.

MAX C. RICHARDSON.

